631708609 has 4 divisors (see below), whose sum is σ = 721952704. Its totient is φ = 541464516.

The previous prime is 631708591. The next prime is 631708621. The reversal of 631708609 is 906807136.

631708609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 631708609 - 2²⁷ = 497490881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (631708699) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45122037 + ... + 45122050.

It is an arithmetic number, because the mean of its divisors is an integer number (180488176).

Almost surely, 2^631708609 is an apocalyptic number.

It is an amenable number.

631708609 is a deficient number, since it is larger than the sum of its proper divisors (90244095).

631708609 is an equidigital number, since it uses as much as digits as its factorization.

631708609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90244094.

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 631708609 is about 25133.8140559685. The cubic root of 631708609 is about 858.0361756490.

The spelling of 631708609 in words is "six hundred thirty-one million, seven hundred eight thousand, six hundred nine".